It is known that a semiconductor manufacturing apparatus is available as one example of a substrate processing apparatus and further that a vertical apparatus is available as one example of the semiconductor manufacturing apparatus. As the substrate processing apparatus of this kind, there is known a substrate processing apparatus which includes a boat as a substrate support member provided within a reaction tube and configured to hold substrates (wafers) in multiple stages and which is configured to process the substrates held by the boat at a predetermined temperature in a process chamber defined within the reaction tube.
There is disclosed a technique in which a plurality of wafers is held by a boat and is inserted into a reaction tube. In this state, films are formed on the wafers by supplying a precursor gas to the wafers disposed within the reaction tube, while maintaining the internal temperature of the reaction tube at a predetermined temperature based on temperature information detected by a temperature sensor as a detection means installed within the reaction tube.
However, in the configuration mentioned above, the temperature sensor is installed within the reaction tube in which film formation is performed. Thus, there may be a case where a film is formed on a quartz-made protective tube for protecting a temperature detection part. Accordingly, a problem is posed in that the protective tube is damaged under the influence of a thermal stress and may become a particle generation source.